Incorporation of oxidatively modified 2'-deoxynucleotide triphosphates by HIV-1 RT on RNA and DNA templates.
Incorporation of oxidatively modified 2'-deoxynucleotide triphosphates by HIV-1 RT on RNA and DNA templates.
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通过 HIV-1 RT 在 RNA 和 DNA 模板上掺入氧化修饰的 2-脱氧核苷酸三磷酸。
DOI：
10.1021/tx010167l
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发表时间：
2002
影响因子：
4.1
通讯作者：
Termini,John
中科院分区：
文献类型：
--
作者：
Wuenschell,GeraldE;Valentine,MichaelR;Termini,John
核苷酸前体库中存在的氧化修饰的脱氧核苷酸三磷酸 (dNoxoTP) 可能由于逆转录酶介导的复制过程中的掺入和模糊碱基配对而导致逆转录病毒诱变。我们检查了 HIV-1 逆转录酶 (HIV-1 RT) 将 5-羟基-2'-脱氧胞嘧啶三磷酸 (5-HO-dCTP) 和 2'-脱氧肌苷三磷酸 (dITP) 掺入相同序列的 DNA 和 RNA 模板上，以评估其致突变潜力。对于每个 dNoxoTP，观察到同源核苷酸位置插入频率的显着变化，通常有利于 RNA 模板。稳态动力学的比较揭示了 5-HO-dCTP 在 RNA 中与 G 相对的掺入偏好高出 10 倍。对于检查的每个碱基位置，dITP 在 RNA 上的插入频率高出 2 至 20 倍。这一总体趋势的一个例外是 HIV-1 RT 在 A 对面插入 5-HO-dCTP，这有利于 DNA 模板 4 倍。脱氧肌苷三磷酸以与 RNA 中的 dGTP 相比高 8 倍的频率插入 C 对面，而在 DNA 模板上，插入频率相同。然而，与其他碱基相反，dITP 的掺入频率相对较低。根据最近利用 5-OH-dCTP 作为抗 HIV 药物的努力，讨论了观察到的 dNoxoTP 掺入的 RNA 模板偏差。
Oxidatively modified deoxynucleotide triphosphates (dNoxoTPs) present in nucleotide precursor pools may contribute to retroviral mutagenesis as a result of incorporation and ambiguous base pairing during reverse transcriptase mediated replication. We have examined the incorporation of 5-hydroxy-2‘-deoxycytosine triphosphate (5-HO-dCTP) and 2‘-deoxyinosine triphosphate (dITP) by HIV-1 reverse transcriptase (HIV-1 RT) on DNA and RNA templates of the same sequence in order to evaluate their mutagenic potential. Significant variations in insertion frequencies at homologous nucleotide positions were observed for each dNoxoTP, in general favoring the RNA template. A comparison of steady-state kinetics revealed a 10-fold preference for 5-HO-dCTP incorporation opposite G in RNA. Insertion frequencies for dITP were 2- to 20-fold greater on RNA for every base position examined. One exception to this general trend was observed for the insertion of 5-HO-dCTP by HIV-1 RT opposite A, which favored the DNA template by 4-fold. Deoxyinosine triphosphate was inserted opposite C with an 8-fold higher frequency compared to dGTP in RNA, while on DNA templates, the incorporation frequencies were equivalent. However, incorporation of dITP opposite other bases was characterized by relatively low frequencies. The RNA template bias observed for dNoxoTP incorporation is discussed in terms of recent efforts to utilize 5-OH-dCTP as an anti-HIV agent.